diff --git a/Gemfile b/Gemfile
index bb94df8..1112b9d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,9 @@
 # frozen_string_literal: true
 
-source "https://rubygems.org"
+if ENV['JEKYLL_ENV'] == 'production'
+  source 'https://gems.sutty.nl'
+else
+  source 'https://rubygems.org'
+end
+
 gemspec